Embodiments of the present invention relate to a device, method, and a program for identifying a location in a network where noise is generated.
When signals are transmitted upstream in a tree-like network such as a cable television broadcast (CATV) and a device is generating noise, the devices upstream from the noise-generating device and other lower-level devices connected to the upper-level device experience communication interference.
Patent Literature 1 Laid-Open Patent Publication No. 2004-72477
Patent Literature 2 Laid-Open Patent Publication No. 2004-40737
Patent Literature 3 Laid-Open Patent Publication No. 2009-10815
Techniques have been disclosed for identifying locations at which noise is being generated (see, for example, Patent Documents 1-3). In one example of a technique used to identify noise-generating devices, switches are provided through which signals are allowed to pass upstream to amplifiers in a network or at which the signals are blocked. When noise is generated, each of the switches is switched to either the passing state or the blocking state, and the noise-generating device is identified by detecting whether or not any noise is present. Therefore, in this technique, switches have to be provided at each branch in the network. Also, the switches must be switched an average of DN/2 times in a network where D is the number of levels and N is the number of branches in communication paths. As a result, the configurations and processes used to detect the locations at which noise is being generated in a network can become complicated using these techniques.